Loading machine

ABSTRACT

A loose rock loading machine having an improved two section bucket or dipper arranged to respond to suitable power and control means to automatically provide an initial, generally horizontal forward loading movement followed by an elevating dumping movement of the bucket onto a conveyor or storage hopper. During shovelling movements a shovel element extends from the bucket to capture large amounts of rock. During the dumping operation the shovel element retracts relative to the bucket. During downward return movement of the bucket to ground level the shovel element stays retracted in the bucket to clear the rock pile.

United States Patent 1 1 Kamner 1 1March 13, 1973 [73] Assignee: Westinghouse Air Brake Company,

Pittsburgh, Pa.

22 Filed: Jan. 12, 1911 21 ApplnNo; 105,904

[52] U.S. Cl. ..2l4/90 R, 214/145 [51] Int. Cl. ..B66b 17/00 [58] Field of Search ..2l4/90 R, 90 A, 145,146 E,

FOREIGN PATENTS OR APPLICATIONS 1,163,690 9/1969 Great Britain ..2l4/90 R Primary ExaminerAlbert J. Malcay Att0rneyFitch, Even, Tobin & Luedka [57] ABSTRACT A loose rock loading machine having an improved two section bucket or dipper arranged to respond to suitable power and control means to automatically provide an initial, generally horizontal forward loading movement followed by an elevating dumping movement of the bucket onto a conveyor or storage hopper. During shovelling movements a shovel element extends from the bucket to capture large amounts of rock. During the dumping operation the shovel element retracts relative to the bucket. During downward return movement of the bucket to ground level the shovel element stays retracted in the bucket to clear the rock pile.

13 Claims, 7 Drawing Figures PATENTEUHAR] 3!.915 720,331 SHEET 2 BF 4 INVENTOR Fig 3 Haj-m J. Kamner 4 PATENTEU'MARl 3191s 3,720,331

SHEET 30F 4 INVENTOR. Haim J. Kamner PATENTEDIARI 3l975 720,331

SHEET u 0F 4 Fig. 7

' INVENTOR- Haim J. Kamner LOADING MACHINE SUMMARY OF THE INVENTION A rock loading machine having a digging and loading bucket assembly mounted on the front end thereof for operation in tunnels or mines with limited clearances. The bucket assembly comprises a shovel element and a receptacle element having suitable power and control means to first advance the bucket assembly in a generally horizontal loading or shovelling movement into the loose rock followed by an elevating upward and backward movement to a dumping position.

Since the entire machine does not have to move back and forth during the loading cycle, loading efficiency is considerably increased over that of prior rock loading machines. Further, discharge of the rock is achieved at reduced bucket elevations which will also improve the loading cycle and permit use of this machine in areas of restricted head room.

Accordingly, a principle object of this invention is to provide an improvedform of mucking machine so constructed and operated that the loading and dumping cycle can be performed while the machine is stationary and at an improved loading rate.

Another object is to provide an improved two section loading and digging bucket for a loading machine arranged to respond to suitable power and control means to automatically provide an initial generally horizontal,

, forward loading movement of the bucket, followed by THE DRAWINGS FIG. 1 is a side elevational view of the front portion of a mobile rock-loading machine embodying the invention.

FIG. 2 is a top plan view of the right front portion of the FIG. 1 apparatus.

FIG. 3 is a side elevational view of the FIG. 2 apparatus.

FIG. 4 illustrates the FIG. 3 apparatus in an elevated position.

FIG. 5 illustrates the FIG. 3 apparatus at the conclusion of the dumping operation.

FIG. 6 is an exploded perspective view of a bucket assembly used in the FIG. 1 apparatus.

FIG. 7 is a fragmentary sectional view on line 7 -7 in FIG. 3.

FIG. 1 shows a rock-loading machine comprising a mobile railway type vehicle 8 supported on track-engaging wheels 10 for movement along railroad tracks 12 in a tunnel 14 under process of construction. The vehicle comprises a suitable main frame or chassis 15 having side walls 16 which define a hopper 17 for receiving loose rock initially taken from the area 18 in front of the loading machine; a bucket assembly 20 and conveyor boom 21 transfer the loose rock from area 18 into hopper 17. The operation is part of a general process wherein the rock is periodically drilled and blasted from the face of the excavation to form a large pile of loose rock in area 18, after which vehicle 8 is moved forwardly along tracks 12 so that its bucket assembly 20 can be powered to dig rock out of the pile and transfer it into the vehicle via a belt conveyor 23 in boom 21. After the pile of rock is depleted vehicle 8 is backed away from the face of the excavation, and new rock is blasted from the face, and so on until the tunnel is finally completed.

Vehicle 8 includes a belt conveyor 22 for moving loose material from the hopper 17 to an elevated discharge point at the rear end of the vehicle 8, not shown. A mine car at the trailing end of vehicle 8 (not shown) receives the discharged rock. Hopper 17 and conveyor 22 preferably have sufficient storage capacity so that bucket assembly 20 can be continuously operated to load rock into hopper 17 while mine cars are being changed at the trailing end of vehicle 8.

BUCKET ASSEMBLY 20 As shown in the exploded view of FIG. 6, the bucket assembly comprises a receptacle 24 having a back wall 25 and parallel side walls 26, and a shovel element 28 having a blade-like bottom wall 30 and parallel side walls 31. Pivot pin connections 33 (FIGS. 1, 3, 4 and 5) go through aligned openings 35 and 36 in the respective members 24 and 28 to permit pivotal extension and retraction of the shovel member relative to the receptacle, as limited by cooperating stops 37 and 39; and by cooperating stop edges 83 and bottom wall 30. The spacing between walls 31 is slightly greater than the spacing between walls 26 so that the shovel and receptacle can freely telescope into one another without any appreciable gaps between the adjacent side walls. Stops 37 may be of U-shaped or channel cross section to slidably receive the edge areas of shovel side walls 31, thereby reinforcing walls 31 against outward bulge under heavy internal rock loads. 1

MECHANISM FOR ELEVATING BUCKET ASSEMBLY 20 As shown in FIGS. 3 and 4, the bucket elevating mechanism comprises a double acting fluid cylinder 38 having a pivotal connection at 40 with a bracket 43 bolted to the side wall 42 of conveyor boom 21; spacer blocks (not visible) space bracket 43 away from boom side wall 42 S0 that the cylinder 33 fits freely into the defined space between wall 42 and bracket 43. The cylinder construction illustrated in FIG. 3 is duplicated on the non-visible side of the boom so that in practice there are two cylinders 38 working in unison.

The cylinder piston rod 44 pivotally connects at 29 with one end of a bell crank 45 that is fulcrummed at 46 on a second outboard plate or bracket 47 suitably formed as a fixed part of boom 21, as by spacer blocks between boom side wall 42 and bracket wall 47. As shown best in FIG. 7, the fixed bracket structure includes an interior fixed wall member 49 located inwardly of wall 47 and a third wall 51 located inwardly of wall 49. Wall 51 fits within end portions of an armate transverse belt cover wall 53 spanning the space between boom side walls 42 (FIG. 2). Wall 51 supports one end of shaft 27 for roll 50; the other end of the shaft is supported by the non-illustrated wall 51 at the other side of the conveyor boom. 7

Still referring to FIG. 7, the space between walls 47 and 49 is occupied by a stub shaft 52 that goes through an opening 54 in the side wall 26 of receptacle 24. The two stub shafts 52 (at both sides of the boom) form pivotal supports for receptacle 24 (and the connected shovel element 28). As shown best in FIGS. 3 and 6, each receptacle side wall carries a bifurcated bracket 55 which receives a pivot pin connector 57 for tie rod 56, said tie rod in turn being pivotally connected with bell crank 45, as at 58.

FIG. 1 illustrates cylinder 38 with its piston fully retracted into the cylinder. In such position the bucket assembly is in a retracted position beneath boom 21, i.e. away from the rock pile in area 18. As hydraulic or pneumatic fluid is supplied to the piston end of cylinder 38 by means of a suitable, manually controlled, fluid circuit (not shown), the piston rod 44 moves to the position of FIG. 3, thereby moving bell crank 45 counterclockwise around its pivot 46 and exerting a pulling action on tie rod 56. The rod pulls receptacle 24 forwardly and upwardly about its pivot axis 52. In the FIG. 3 position shovel element 28'has its blade wall 30 dug into the rock pile so that a quantity of rock is within the confines of the bucket assembly 20. The assembly has not yet lifted the confined rock out of the pile.

As piston 44 is extended further out of cylinder 38 the bucket assembly 20 is elevated to the FIG. 4 full line position clear of the rock pile. The bucket assembly is, however, still below the level of the belt conveyor 23 so that the confined rock is still within the bucket.

Further extension of piston 44 causes the bucket assembly to be elevated and overturned, as shown in dotted lines at 59 and 61 in FIG. 4; the overturned position is also shown in full lines in FIG. 5. In the overturned position of the bucket assembly the rock is fully discharged onto the continuously moving belt conveyor 23 where it can be carried rearwardly toward hopper 17 (FIG. I).

CONVEYOR 23 FIG. 1 shows belt conveyor 23 trained around the large idler roll 50 at the front of boom 21, a large powered roll 62 at the rear of the boom, and small idler tension roll 64 intermediate the ends of the boom. Conveyor movement in the arrow 66 direction is obtained from a motor-speed reducer power unit 65 mounted on the underside of the boom; the drive between unit 65 and roll 62 may be conveniently provided by chainsprocket mechanisms illustrated by numeral 68.

Continuous movement of belt 23 in the arrow 66 direction causes collected rock to be carried on the upper run of the belt from the forward end of the boom to the rearward end, from whence it is discharged onto a pan 69 secured to the discharge end of boom 21. Pan 69 guides the rock onto the main conveyor 22.

It would perhaps be possible to use a single conveyor instead of two separate conveyors 23 and 22. However, in that event some problems would be encountered in powering the boom unit 21 up and down (using fluid cylinder 70) and side-to-side (using fluid cylinder 72). Such movements of the boom unit are required in order for the bucket to load loose rock along both sides of the track 12.

SHOVEL 28 OPERATION As shown in FIG. 6, the shovel side walls 31 are extended rearwardly beyond the heel area 74 of the shovel blade wall 30, and openings 77 are formed in the side wall extensions to receive pins 75 (FIG. 3) which pivotally connect the shovel element to fluid cylinders 76. The piston rod 78 of each fluid cylinder 76 extends upwardly to a pivotal connection at 79 with the boom structure 21. As shown in FIG. 7, each piston rod 78 extends into the space between boom walls 49 and 51. The general arrangement permits each fluid cylinder assembly 76 to pivot around the pivot 79 axis from the FIG. 1 position through the FIG. 3 and 4 positions to the upper limit position of FIG. 5. During this movement the piston rod passes through the rotational axis of roll 50 and the swing axis 52 of receptacle 24; due to the spaced character of walls 49 and 51 (FIG. 7) there is no obstruction to such movement.

The full line retracted position of FIG. 1 corresponds with the dotted line position 80a of FIG. 3. As main cylinder 38 is energized to move receptacle 24 from its dotted line retracted position 80a the pivot pins 33 and move through arcs designated by numerals 82 and 84. Pivot 79 is located slightly behind swing axis 52, and pivot 75 is located slightly behind pivot 33. Therefore, piston-cylinder assembly 76 functions as a link paralleling the linkage between pivots 52 and 33 (during the limited arcuate travels at 82 and 84). The result is that the FIG. 3 full line position of shovel element 28 can be reached without change in the length of the cylinder 76 piston rod 78 assembly which is fully contracted. This means that no power fluid need be added to cylinder 76 during the FIG. 3 stroke.

During the FIG. 3 stroke the shovel blade wall 30 rides along the ground into the rock pile to underlie the loose rock. As this occurs the blade unfolds or extends from receptacle 24. Thus, in dotted line position 800 the blade wall 30 is tucked into receptacle 24 against stop edges 83 of receptacle side walls 26, whereas in the full line position the blade wall is extended forwardly and outwardly beyond wall edges 83.

In the FIG. 3 full line position the shovel element 28 is prevented from further extension or unfolding out of the bucket receptacle by abutment of the cooperating stops 37 and 39. During the FIG. 3 stroke power fluid is normally supplied only to cylinder 38 and no power fluid is supplied to cylinder 76; the bucket assembly will move from dotted line position a to the FIG. 3 full line position. Such movement of the bucket will cause maximum quantities of rock, stone, earth, coal, etc. to be loaded into the bucket.

Movement of the bucket assembly from the FIG. 3 position to the FIG. 4 full line position may be accomplished by cylinder 38; during such movement no power fluid necessarily needs to be supplied to cylinder 76 because the stops 37 and 39 prevent any undesired outfolding of the shovel relative to receptacle 24. As pressure fluid is added to cylinder 38 the bucket assembly can move to the elevated position 59 wherein rock, etc. is gravitationally discharged onto cover 53 and conveyor 23. Receptacle back wall 25 has its edge closely adjacent cover 53 man positions of the bucket assembly so that substantially none of the material can escape through the defined crack between elements 25 and 53.

In normal operation, moving the bucket assembly from the FIG. 4 position to the FIG. 5 position, cylinder 38 elevatably swings the bucket along arc 59b to position 59 which corresponds to the end of piston rod 44s travel. Upon arriving at position 59, shovel element 28 will drop to position 61, due to gravity and inertia. The shovel element 28 will then be in abutting relationship with stop edges 83 of the receptacle 24 and fully retracted into the receptacle. In this mode of operation, fluid in cylinders 76 is allowed to pass freely from one end of the cylinder to the other end by way of a fluid circuit.

In some instances, however, it may be desirable to move from the FIG. 4 position to the FIG. 5 position along arc 59a. The primary advantage to this path is, of course, reduced discharge height which enables the loader to be used in lower height tunnels. The fluid circuit is activated to energize (extend) fluid cylinders 76 so that the tip of blade wall 30 moves along arc 59a instead of arc 59b. Blade 30 undergoes a leftward retraction, as viewed in FIG. 4, into receptacle 24. This provides an added benefit of positively crowding or displacing the rock, onto conveyor 23. Blade 30 acts as a piston to assist gravitational discharge of the material. FIG. 5 illustrates the final position of parts after complete discharge of material.

RETURNING THE BUCKET ASSEMBLY TO GROUND LEVEL The empty bucket assembly may be returned from the FIG. 5 dumping position down to the FIG. I restart position by feeding pressure fluid into the piston rod ends of cylinders 38. This action achieves a clockwise movement of crank 45 and a pushing effect of rod 56 on receptacle 24; the empty receptacle is thereby swung downwardly about swing axis 52.

During the downward resetting movement of bucket 20, it is desired that shovel element 28 remain retracted within receptacle 24, so that the tip of blade 30 follows an are 590. The fluid cylinder 76 must therefore, undergo a contraction in its length to achieve the necessary decrease in spacing between pivots 75 and 79. In this movement, fluid may be permitted to circulate from one end of cylinder 76 to its other end via the fluid circuit. However, with the pivot arrangement provided, (whereby the shovel element 28 is in an over center position relative to pivot pin 33 during most of the resetting movement) and with the centrifugal forces acting on the center of gravity of shovel element 28, the shovel element 28 is held retracted relative to the receptacle 24 during the buckets movement to the FIG. 1 position.

BOOM 21 MOVEMENT Referring to FIG. 1, boom 21 is a cantilever member having a swingable connection with a pedestal structure 90 about a horizontal axis generally in line with the axis of-roll 62. The boom can thereby swing in a vertical are from the depressed position designated by numetal 92 through the full line normal position to a nonillustrated elevated position, not shown. Power means for thisvertical movement may be provided by a fluid cylinder 70 having a pivotal connection 96 with a table member 98 which carries the aforementioned pedestal 90.

Table member 98 is rotationally supported on a central post (not shown) which extends upwardly from an overhanging platform 99 carried by chassis 15. The table member is equipped with suitable rollers 100 which rollon the upper face of platform 99 to bear the weight of the boom and bucket assembly. Aforementioned fluid cylinder 72 provides a power means for swinging table 98 and boom structure 21 in a horizontal arc.

The illustrated apparatus is particularly designed for use in tunnels which may vary in height and width, for example, widths between 10 feet and 25 feet, and heights between 8 feet and 25 feet. The width of boom 21 is only on the order of 4 feet; therefore, in order for the boom and bucket assembly to reach loose rock at the sides of the tunnel, it is necessary to swing the boom horizontally around the post axis, as by energizing fluid cylinder 72.

Ordinarily the height of the tunnel does not affect the operation of the apparatus as long as the tunnel is high enough to accommodate the arc 59a taken by the tip of blade 30 (FIG. 4). However, on occasion the rock pile in front of the machine may be so high that it is impractical for the shovel to attack the rock pile at its base. In such occasions it may be more practical to raise the boom, as by energizing cylinder (FIG. 1), so that the shovel can dig into the pile at a point above its base. On other occasions the floor of the tunnel may slope downwardly relative to rail tracks 12, in which event cylinder 70 may be exhausted of fluid to lower boom 21 and enable the shovel to attack the rock pile below the track 12 elevation, as shown in dotted lines in FIG. 1.

APPARATUS USED IN ST TION RY PosrrroN Vehicle 8 (including chassis 15, boom 21 and bucket assembly 20) may weigh in the neighborhood of twenty five tons unloaded. The inertia of such a mass is such that it is difficult to accelerate the entire vehicle quickly from a rest position or to decelerate the vehicle quickly from a moving position to a rest position. Therefore, it is desirable that the rock-loading operation be carried out so that chassis 15 remains generally motionless as bucket 24 cycles back and forth between its up and down positions.

The illustrated apparatus is such that shovel movement (FIG. 3) is accomplished while chassis 15 is stationary. The leading edge of blade 30 moves generally in a horizontal direction to penetrate more deeply into the pile than if it were to move in an upward arc about swing axis 52. This potential for deeper penetration means a greater removal of rock per given load cycle, and also more cycles before vehicle chassis 15 has to be repositioned. The ability to achieve more consecutive cycles is partly due to the ability of the shovel to be retracted into receptacle 24 during the downward reset stroke (FIG. 5 to FIG. 1). Thus, in the retracted mode of blade 30 there is assurance that the blade will clear the pile of rock, coal, etc. on the downstroke even though the bucket swings quite close to the pile. This means that vehicle 8 can be moved into close proximity to the rock pile, and that multiple shovel strokes can be achieved before the pile is out of reach of blade 30.

CYCLEYTIME The illustrated machine has a reduced cycle time primarily because only the. bucket assembly 20 has to be moved during each cycle; i.e.,. vehicle 8 and boom 21 remain motionless. A further factor contributing to reduced cycle time is the small swing radius of the bucket about swing axis 52. Blade 30 can reach out to gather in the loose material, but once the material is in the bucket the cylinder 76 can be actuated to cause blade 30 to move the material further into the bucket nearer axis 52. By thus repositioning the material it is possible to reduce the moment arm of the load around axis52 so that the bucket assembly can be operated at a higher speed and with less effort.

A further factor which can contribute to faster cycle time is the piston action of blade 30 which assists gravity forces in ejecting the loose material onto conveyor 23. Due to the ejection action the material in the receptacle 24 does not have to swing through quite as large an are as would otherwise be required; the lessened arc can achieve dumping in a shorter period of time.

I ROOTING OPERATION In some instances, blade 30 can be made to more easily penetrate the pile of rock if the bucket assembly is given a side-to-side jiggling motion or an up-anddown jiggling motion, commonly called rooting action. With the illustrated apparatus cylinders 72 can be used to obtain the side-to-side motion, and cylinder 70 can be used to obtain the up-and-down motion. Cylinders 76 may also be used to provide some additional rooting action. Further, a limited rooting action is obtained by the normal pivotable movement of the bucket assembly 20, whereby the bottom or heel area 74 of the blade 30 isurged upward when advancing in a loading movement. Cylinder 70 is arranged to permit this upward movement and normally limits any downward movement. Rooting operations permit the blade to work under large rocks or chunks of material.

ACTION OF CYLINDERS 76 It is believed that cylinder 76 can be a double-acting fluid cylinder, or a single-acting fluid cylinder, or merely a non-powered device. If member 76 is constructed as a double-acting cylinder it can be power-extended during the latter stages of the FIG. 4 dumping movement, and power-retracted during the downward reset stroke (from the FIG. 5 to FIG. 3 position). If member 76 is constructed as a single-acting cylinder it can be .power-extended-during the latter stages of the FIG. 4

dumping movement; the pressure chamber can be controllably vented during the reset stroke. If member 76 is constructed as a non-powered device it will act merely as a variable length link; during the FIG. 3 shovel movement the shovel element 30 will automatically unfold from the bucket, during the FIG. 4 dumping movement the shovel element will retract into the bucket by gravity action, and during the reset stroke the shovel element will remain retracted relative to the bucket.

I claim as my invention:

1. In a loading machine for loose material comprising a mobile frame having a load-receiving structure thereon adapted to be moved into a location adjacent a pile of loose material to be loaded; the combination therewith of a bucket-shovel assembly comprising a shovel element and a bucket element carried by the mobile frame for cyclic movements, and movement means operable to advance the bucket-shovel assembly from a first lowered retracted position wherein the shovel element is tucked into the bucket element to a second lowered advanced position wherein the shovel element is extended from the bucket element in a generally straight-line direction to underlie the loose load material while the mobile frame is stationary, thence upwardly to a third elevated load-discharging position, and thence back down to the first position wherein the shovel element is tucked into the bucket element.

2. In a loading machine for loose material comprising a mobile frame having a load-receiving structure thereon adapted to be moved into a location adjacent a pile of loose material be loaded, the combination therewith of a bucket-shovel assembly comprising a shovel element and a bucket element carried by the mobile frame for cyclic movements, and movement means operable to advance the bucket-shovel assembly from a first lowered retracted position wherein the shovel element is tucked into the bucket element to a second lowered advanced position wherein the shovel element is extended from the bucket element to underlie the loose load material, thence upwardly to a third elevated load-discharging position, and thence back down to the first position wherein the shovel element is tucked into the bucket element, said movement means comprising a fluid cylinder operable to raise and lower the bucket element, and an extensible link, said fluid cylinder having a tie element connection with the bucket element such that advancement of the shovel element into the loose pile is effected by a pulling force of the tie element on the bucket element under the motive action of the fluid cylinder, said extensible link extending between spaced pivotal connections on the mobile frame and shovel element.

3. The machine of claim 2 wherein the extensible link comprises a second fluid cylinder operably to extend and retract the shovel relative to the bucket.

4. In a loading machine for loose material comprisingv a mobile frame having a ground wheel-equipped hopper structure and a cantilever boom structure projecting forwardly therefrom so that the boom structure can be positioned above and in proximity to a pile of loose material to be loaded, said boom structure having side walls defining a load-receiving trough structure; the improvement therewith of a bucket-shovel assembly swingably connected to the forward end portion of the boom structure for movement into the pile of loose material, said bucket-shovel assembly comprising a shovel element and a bucket element, movement means operable to advance the bucket-shovel assembly from a first lowered retracted position wherein the shovel element is tucked into the bucket element to a second lowered advanced position wherein the shovel element is extended from the bucket element to underlie the loose load material, thence upwardly to a third elevated load-discharging position, and thence back down to the first position wherein the shovel element is tucked into the bucket element, and said mobile frame having power means thereonfor raising and lowering the boom structure about its cantilever connection with the ground wheel-equipped structure, whereby the shovel element can be moved into the pile of loose material at different elevations relative to the base of the pile.

5. In a loading machine comprising a mobile frame having a conveyor extending rearwardly therealong to move loose material in a front-to-rear direction; the combination therewith of a digging and loading bucket assembly comprising a shovel element and a receptacle element, said receptacle element being pivotally mounted at the forward end of the conveyor on a transverse supporting pivot, said shovel element and said receptacle element having hinged interconnections for relative movement therebetween, said shovel element being arranged for slidable engagement with the ground in a load-receiving position, and power and control means operatively associated with said loading bucket assembly to automatically provide a generally straight-line advance loading movement of the said shovel element while the mobile frame is stationary and said receptacle element is elevatably swung around said transverse supporting pivot.

6. The machine of claim in which the power and control means is adapted to elevatably swing both elements of the loading bucket upward and backwards in a dumping movement after the shovel element has completed its forward loading movement, to discharge collected material loaded during the loading movement onto the conveyor.

7. The machine of claim 5 wherein said shovel element comprises a pair of spaced side walls interconnected by a bottom blade wall, and said receptacle element comprises a pair of side walls interconnected by a back wall; the aforementioned side walls being arranged in overlapping relationship to form continuous bucket side walls in all positions of said relative movement.

8. The loading machine of claim 6 wherein the power and control meanscomprises first power means for overturning the receptacle during the dumping movement, and second power means for pivoting the shovel so that its bottom wall moves toward the receptacle back wall during the overturning operation, whereby the shovel promotes a forced ejection of material from the receptacle. I

9. The loading machine of claim 8 wherein the two power means and the pivot arrangement maintain the shovel bottom wall closely adjacent the receptacle back wall during downward movement of the bucket assembly back to ground level, whereby the shovel is enabled to clear loose material in the area forwardly of the machine.

10. A loading machine for loose material comprising a mobile main frame having a conveyor boom for moving loose material in a front-to-rear direction; cantilever means supporting the conveyor boom for arcuate vertical and horizontalmovement relativeto the frame; a digging and loading bucket comprising a receptacle having upper side wall areas thereof swingably connected to the forward end of the boom, and a shovel having a heel section swingably connected to lower side wall areas of the receptacle so that the shovel can slide along the ground to cause its blade area to underlie loose material as the receptacle swings forwardly and upwardly; first fluid cylinder means operably trained between the boom and receptacle for raising and lowering same about its swing axis; second fluid cylinder means operably trained between the boom and heel area of the shovel for pivoting the shovel rearwardly into the receptacle after the receptacle has lifted clear of the pile; said first and second fluid cylinders having sufficient strokes as to simultaneously cause the receptacle to overturn and the shovel to forcefully pivot into the receptacle, whereby the contained material is discharged onto the boom conveyor; said fluid cylinders being arranged so that the receptacle can be lowered from the overturned position with the shovel still pivoted into the receptacle interior, whereby the shovel is prevented from striking the loose pile of material on its downstroke.

11. The machine of claim 10 wherein the boom comprises side walls defining a trough structure, an idler roll disposed at the forward end of the trough structure, and a conveyor belt trained around the roll for movement of loose material in a rearward direction; the boom and receptacle being swingably connected so that the receptacle generally turns: on the idler roll axis, said receptacle having a backwall that has close edge clearance relative to the belt whereby little or no material can escape from the receptacle through the receptacle-belt joint.

12. In a loading machine having a load-receiving structure; the combination therewith of a bucket as sembly swingably suspended from said load-receiving structure for movement from a ground level position to a dumping position, said bucket assembly comprising a receptacle element and a shovelelement, said receptacle element having a pair of spaced side walls interconnected by a back wall, said shovel element having spaced side walls interconnectedby a bottom blade wall, said shovel element being moveable to extend from said receptacle element to gather loose material and being retractable into said receptacle element such that said walls of said receptacle and shovel elements are in generally side-by-side relation, first power means for overturning said receptacle element during a dumping movement, and second power means for effecting said retractable movement of said shovel element so that its said bottom wall moves toward said back wall of said receptacle element during said dumping movement and said shovel element remains in said retracted position during return from said dumping movement to ground level.

13. The combination of claim 12 wherein said second power means is adapted to effect extending movement of said shovel element from said receptacle element to gather loose material when said load-receiving structure is stationary. 

1. In a loading machine for loose material comprising a mobile frame having a load-receiving structure thereon adapted to be moved into a location adjacent a pile of loose material to be loaded; the combination therewith of a bucket-shovel assembly comprising a shovel element and a bucket element carried by the mobile frame for cyclic movements, and movement means operable to advance the bucket-shovel assembly from a first lowered retracted position wherein the shovel element is tucked into the bucket element to a second lowered advanced position wherein the shovel element is extended from the bucket element in a generally straight-line direction tO underlie the loose load material while the mobile frame is stationary, thence upwardly to a third elevated load-discharging position, and thence back down to the first position wherein the shovel element is tucked into the bucket element.
 1. In a loading machine for loose material comprising a mobile frame having a load-receiving structure thereon adapted to be moved into a location adjacent a pile of loose material to be loaded; the combination therewith of a bucket-shovel assembly comprising a shovel element and a bucket element carried by the mobile frame for cyclic movements, and movement means operable to advance the bucket-shovel assembly from a first lowered retracted position wherein the shovel element is tucked into the bucket element to a second lowered advanced position wherein the shovel element is extended from the bucket element in a generally straight-line direction tO underlie the loose load material while the mobile frame is stationary, thence upwardly to a third elevated load-discharging position, and thence back down to the first position wherein the shovel element is tucked into the bucket element.
 2. In a loading machine for loose material comprising a mobile frame having a load-receiving structure thereon adapted to be moved into a location adjacent a pile of loose material be loaded, the combination therewith of a bucket-shovel assembly comprising a shovel element and a bucket element carried by the mobile frame for cyclic movements, and movement means operable to advance the bucket-shovel assembly from a first lowered retracted position wherein the shovel element is tucked into the bucket element to a second lowered advanced position wherein the shovel element is extended from the bucket element to underlie the loose load material, thence upwardly to a third elevated load-discharging position, and thence back down to the first position wherein the shovel element is tucked into the bucket element, said movement means comprising a fluid cylinder operable to raise and lower the bucket element, and an extensible link, said fluid cylinder having a tie element connection with the bucket element such that advancement of the shovel element into the loose pile is effected by a pulling force of the tie element on the bucket element under the motive action of the fluid cylinder, said extensible link extending between spaced pivotal connections on the mobile frame and shovel element.
 3. The machine of claim 2 wherein the extensible link comprises a second fluid cylinder operably to extend and retract the shovel relative to the bucket.
 4. In a loading machine for loose material comprising a mobile frame having a ground wheel-equipped hopper structure and a cantilever boom structure projecting forwardly therefrom so that the boom structure can be positioned above and in proximity to a pile of loose material to be loaded, said boom structure having side walls defining a load-receiving trough structure; the improvement therewith of a bucket-shovel assembly swingably connected to the forward end portion of the boom structure for movement into the pile of loose material, said bucket-shovel assembly comprising a shovel element and a bucket element, movement means operable to advance the bucket-shovel assembly from a first lowered retracted position wherein the shovel element is tucked into the bucket element to a second lowered advanced position wherein the shovel element is extended from the bucket element to underlie the loose load material, thence upwardly to a third elevated load-discharging position, and thence back down to the first position wherein the shovel element is tucked into the bucket element, and said mobile frame having power means thereon for raising and lowering the boom structure about its cantilever connection with the ground wheel-equipped structure, whereby the shovel element can be moved into the pile of loose material at different elevations relative to the base of the pile.
 5. In a loading machine comprising a mobile frame having a conveyor extending rearwardly therealong to move loose material in a front-to-rear direction; the combination therewith of a digging and loading bucket assembly comprising a shovel element and a receptacle element, said receptacle element being pivotally mounted at the forward end of the conveyor on a transverse supporting pivot, said shovel element and said receptacle element having hinged interconnections for relative movement therebetween, said shovel element being arranged for slidable engagement with the ground in a load-receiving position, and power and control means operatively associated with said loading bucket assembly to automatically provide a generally straight-line advance loading movement of the said shovel element while the mobile frame is stationary and said receptacle element is elevatably swung around said transverse supporting pivot.
 6. The machine of claim 5 In which the power and control means is adapted to elevatably swing both elements of the loading bucket upward and backwards in a dumping movement after the shovel element has completed its forward loading movement, to discharge collected material loaded during the loading movement onto the conveyor.
 7. The machine of claim 5 wherein said shovel element comprises a pair of spaced side walls interconnected by a bottom blade wall, and said receptacle element comprises a pair of side walls interconnected by a back wall; the aforementioned side walls being arranged in overlapping relationship to form continuous bucket side walls in all positions of said relative movement.
 8. The loading machine of claim 6 wherein the power and control means comprises first power means for overturning the receptacle during the dumping movement, and second power means for pivoting the shovel so that its bottom wall moves toward the receptacle back wall during the overturning operation, whereby the shovel promotes a forced ejection of material from the receptacle.
 9. The loading machine of claim 8 wherein the two power means and the pivot arrangement maintain the shovel bottom wall closely adjacent the receptacle back wall during downward movement of the bucket assembly back to ground level, whereby the shovel is enabled to clear loose material in the area forwardly of the machine.
 10. A loading machine for loose material comprising a mobile main frame having a conveyor boom for moving loose material in a front-to-rear direction; cantilever means supporting the conveyor boom for arcuate vertical and horizontal movement relative to the frame; a digging and loading bucket comprising a receptacle having upper side wall areas thereof swingably connected to the forward end of the boom, and a shovel having a heel section swingably connected to lower side wall areas of the receptacle so that the shovel can slide along the ground to cause its blade area to underlie loose material as the receptacle swings forwardly and upwardly; first fluid cylinder means operably trained between the boom and receptacle for raising and lowering same about its swing axis; second fluid cylinder means operably trained between the boom and heel area of the shovel for pivoting the shovel rearwardly into the receptacle after the receptacle has lifted clear of the pile; said first and second fluid cylinders having sufficient strokes as to simultaneously cause the receptacle to overturn and the shovel to forcefully pivot into the receptacle, whereby the contained material is discharged onto the boom conveyor; said fluid cylinders being arranged so that the receptacle can be lowered from the overturned position with the shovel still pivoted into the receptacle interior, whereby the shovel is prevented from striking the loose pile of material on its downstroke.
 11. The machine of claim 10 wherein the boom comprises side walls defining a trough structure, an idler roll disposed at the forward end of the trough structure, and a conveyor belt trained around the roll for movement of loose material in a rearward direction; the boom and receptacle being swingably connected so that the receptacle generally turns on the idler roll axis, said receptacle having a backwall that has close edge clearance relative to the belt whereby little or no material can escape from the receptacle through the receptacle-belt joint.
 12. In a loading machine having a load-receiving structure; the combination therewith of a bucket assembly swingably suspended from said load-receiving structure for movement from a ground level position to a dumping position, said bucket assembly comprising a receptacle element and a shovel element, said receptacle element having a pair of spaced side walls interconnected by a back wall, said shovel element having spaced side walls interconnected by a bottom blade wall, said shovel element being moveable to extend from said receptacle element to gather loose material and being retractable into said receptacle eleMent such that said walls of said receptacle and shovel elements are in generally side-by-side relation, first power means for overturning said receptacle element during a dumping movement, and second power means for effecting said retractable movement of said shovel element so that its said bottom wall moves toward said back wall of said receptacle element during said dumping movement and said shovel element remains in said retracted position during return from said dumping movement to ground level. 